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111.
Philippe Grangier Anders Karlsson John Rarity 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,15(1):3
The collective phenomena of quantum interference, including wave particle duality and apparent non-locality, have intrigued
the physics community for many years. It is only recently that we have begun to turn these somewhat counter intuitive quantum
phenomena to good use. A leading force in that direction is quantum cryptography - absolute secure key exchange encoding data
on the polarisation or phase of individual photons, or using the quantum correlations between pairs of particles. Technologies
are now implemented to bring the various forms of quantum cryptography to commercial application. At the same time the possibility
of communications applications has stimulated the study of a variety of novel quantum interference phenomena. Quantum information
experiments involving two, three and four photons are planned and a novel Field of continuous variable (many photon) quantum
information has emerged.
These various aspects of quantum cryptography are considered in the conference “QUICK: Quan- tum interference and cryptographic
keys: novel physics and advancing technologies", taking place in Cargese from April 7 to 13, 2001. Following that conference,
we invite submission of original papers to a special issue of the European Physical Journal D, on the following topics: -
quantum cryptography technologies, - quantum cryptography systems, - free space quantum cryptography and satellites, - pair-photon
sources and multiphoton interference, - single photon sources, - continuous variable quantum information, - security aspects,
- cryptographic protocols, - entanglement purification in cryptographic schemes, - novel physics and quantum gates for photonic
qubits.
The submitted articles should be sent to the EPJ D Editorial Office in Orsay. The deadline is July 15, 2001. We look forward to a stimulating special issue. 相似文献
112.
Yves Leterrier Jérémy Thivolle Fabiane Oliveira Jan‐Anders Månson Lorenz Gubler Hicham Ben youcef Lukas Bonorand Günther Scherer 《Journal of Polymer Science.Polymer Physics》2013,51(15):1139-1148
The influence of temperature and moisture activity on the viscoelastic behavior of fluorinated membranes for fuel cell applications was investigated. Uncrosslinked and crosslinked ethylene tetrafluoroethylene (ETFE)‐based proton‐conducting membranes were prepared by radiation grafting and subsequent sulfonation and their behavior was compared with ETFE base film and commercial Nafion® NR212 membrane. Uniaxial tensile tests and stress relaxation tests at controlled temperature and relative humidity (RH) were carried out at 30 and 50 °C for 10% < RH < 90%. Grafted films were stiffer and exhibited stronger strain hardening when compared with ETFE. Similarly, both uncrosslinked and crosslinked membranes were stiffer and stronger than Nafion®. Yield stress was found to decrease and moisture sensitivity to increase on sulfonation. The viscoelastic relaxation of the grafted films was found to obey a power‐law behavior with exponent equal to ?0.04 ± 0.01, a factor of almost 2 lower than ETFE, weakly influenced by moisture and temperature. Moreover, the grafted films presented a higher hygrothermal stability when compared with their membranes counterparts. In the case of membranes, a power‐law behavior at RH < 60% was also observed. However, a markedly different behavior was evident at RH > 60%, with an almost single relaxation time exponential. An exponential decrease of relaxation time with RH from 60 s to 10 s was obtained at RH ≥ 70% and 30 °C. The general behavior of grafted films observed at 30 °C was also obtained at 50 °C. However, an anomalous result was noticed for the membranes, with a higher modulus at 50 °C when compared with 30 °C. This behavior was explained by solvation of the sulfonic acid groups by water absorption creating hydrogen bonding within the clusters. A viscoelastic phase diagram was elaborated to map critical conditions (temperature and RH) for transitions in time‐dependent behavior, from power‐law scaling to exponential scaling. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1139–1148 相似文献
113.
A set M of edges of a graph G is a matching if no two edges in M are incident to the same vertex. A set S of vertices in G is a total dominating set of G if every vertex of G is adjacent to some vertex in S. The matching number is the maximum cardinality of a matching of G, while the total domination number of G is the minimum cardinality of a total dominating set of G. In this paper, we investigate the relationships between the matching and total domination number of a graph. We observe that the total domination number of every claw-free graph with minimum degree at least three is bounded above by its matching number, and we show that every k-regular graph with k?3 has total domination number at most its matching number. In general, we show that no minimum degree is sufficient to guarantee that the matching number and total domination number are comparable. 相似文献
114.
Bostrom Anders; Golub Mikhail 《The Quarterly Journal of Mechanics and Applied Mathematics》2009,62(1):39-52
Elastic SH wave propagation in a layered anisotropic plate withinterface damage is modelled in several steps. A single interfacecrack between two half-spaces is first studied and an explicitsolution for the crack-opening displacement is obtained at lowfrequencies. This is then generalised to a random distributionof cracks at the interface and the result is reformulated asa spring boundary condition. As an example of its usefulness,this boundary condition is then used in the derivation of aplate equation by expanding the displacements in power seriesin the thickness coordinate. 相似文献
115.
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118.
Anders A. Anders S. Hantzsche E. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1989,17(5):653-656
Validity conditions for complete and partial local thermodynamic equilibrium (CLTE and PLTE) of homogeneous, time-dependent, and optically thin plasmas are derived. For Cu I, electron densities of n e⩾(5×1022-5×1023 ) m-3 are required for the establishment of CLTE. For Cu I and Cu II, n e⩾(5×1021-5×1021 -5×1022) m-3 is necessary for PLTE (for electron temperatures of 1-2 eV). Application to low-current copper vapor arcs in vacuum shows that CLTE can be expected for r <200-600 μm (r =distance from the cathode spot). A further limitation follows for temperatures of 2 eV or higher if diffusion effects are taken into consideration. Consequently, the use of the LTE formulas in plasma spectroscopy of low-current vacuum arcs is very limited 相似文献
119.
The cathode processes of electric ares on cleaned Cu cathodes were investigated in the transition region between vacuum and atmospheric pressure (argon). The plasma density in the cathode plane was estimated by probe measurements to be n = r are current, r – distance from the spot). It was observed that several cathode spot parameters have an extremum at p ~ 104 Pa. The crater diameter has a minimum independently of the cathode temperature. The diffusion constant of the chaotic motion determined by framing photographs was found to have a maximum. Some additional, large displacements occurred at that pressure. The diameter of the bright plasma cloud obtained by open-shutter photographs showed a maximum, the current per spot was found to decrease from 20 A in vacuum to 10 A at atmospheric pressure. It is thus concluded that the spot with the smallest crater radius and a low current per spot, occurring at ~ 104 Pa, represents the single spot, whereas the spot at higher pressures, and probably also in vacuum, has a complicated nature where the large craters are formed by a cooperation of single spots. 相似文献
120.
Targeted analysis of protein citrullination using chemical modification and tandem mass spectrometry
Maria Stensland Anders Holm Andrea Kiehne Burkhard Fleckenstein 《Rapid communications in mass spectrometry : RCM》2009,23(17):2754-2762
Protein citrullination originates from enzymatic deimination of polypeptide‐bound arginine and is involved in various biological processes during health and disease. However, tools required for a detailed and targeted proteomic analysis of citrullinated proteins in situ, including their citrullination sites, are limited. A widely used technique for detection of citrullinated proteins relies on antibody staining after specific derivatization of citrulline residues by 2,3‐butanedione and antipyrine. We have recently reported on the details of this reaction. Here, we show that this chemical modification can be utilized to specifically detect and identify citrullinated peptides and their citrullination sites by liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. Using model compounds, we demonstrate that in collision‐induced dissociation (CID) a specific, modification‐derived fragment ion appears as the dominating signal at m/z 201.1 in the MS/MS spectra. When applying electron transfer dissociation (ETD), however, the chemical modification of citrulline remained intact and extensive sequence coverage allowed identification of peptides and their citrullination sites. Therefore, LC/MS/MS analysis with alternating CID and ETD has been performed, using CID for specific, signature ion‐based detection of derivatized citrullinated peptides and ETD for sequence determination. The usefulness of this targeted analysis was demonstrated by identifying citrullination sites in myelin basic protein deiminated in vitro. Combining antibody‐based enrichment of chemically modified citrulline‐containing peptides with specific mass spectrometric detection will increase the potential of such a targeted analysis of protein citrullination in the future. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献